Electric drive mechanism



Mag' 29, 1923.

G. E. HAMPTON ELECTRIC DRIVE MECHANISM Original Filed Jan. l0. 1917 2 Sheets-Sheet l INVENTOR.

WITNESS Maly 29, 1923. 1,456,550

G. E. HAMPTON ELECTRI C DRIVE MECHANISM Original Filed Jan. l0, 1917 ZSheets-Sheet 2 Patented May 29, 1923.

UNITED STATES PATENT oFF1cE..

GEORGE E. HAMPTON, OF PITTSBURGH, PENNSYLVANIA, ASSIGNOR, BY DIRECT AND MESNE ASSIGNMENTS,TO CENTRAL ELECTRIC TOOLuCOMIjANY, 0F PITTSBURGH,

PENNSYLVANIA, A CORPORATION OIF'PENNSYLVANIA Application mea January 1o, 1917, serial No. 14.1,

siding at Pittsburgh, county of Allegheny,y

and State of Pennsylvania, have invented certain new and useful Improvements in .Electric Drive Mechanism, of which the follow-ing is a. specification. i This invention relates to an electric drive mechanism wherein a reciprocatory element is' employed for the production of work, and is designed primarily for electric hammers, although it is to be understood that it is adapted for any purposes wherein it is found applicable, and the invention has'lfor its jobject to provide a drive mechanism, in a manner as hereinafter 'seti forth. including means to set up an electric ycurrent traveling alternately through two solenoids for reciprocating an element to'impact on a tool to operate the latter, and. said mechanism including means, associated with said element and independent of the'solenoids. to add t0 the impact between the element and the 'l' tool thus increasing thejcapacity of the latter iniperforming its function.

Further objects of theJ invention are to provide an electric drive mechanism which is simple in its constructionand arrangement, strong, durable, efficient and convenient in its operation, readily aembl'ed, and comparatively inexpensive to set 11p.

Vith the foregoing and other objects in View the invention 'consists of the novel construction, combination and arrangement of parts, as'hereinafter more specifically de-u scribed and illustrated in the accompanying drawings, wherein is shown an embodiment of the inventionbut it is to be understood that changes, variations and modifications can be 'resorted towhich come within the of an electric drive mechanism in accord'- ance with this invention and showing the adaptation thereof in connection with an electric hammer.

Figure 2 is a diagram illustrating the arrangement of the circuit wires with respect to the solenoids.

ELECTRIC DRIVE MEcHANIsM.

584. Renewed August 30, 1921. Serial No. 497,048.

Figure 3 is a .section on line III-111, Figjure '1.,

Figure 4 is an end view. Figure 5 is a diagram illustrating the cir- Vcuit arrangement for an Ai C. hammer.v

Figure v6 is' a diagram illustrating the circuit arrangement' for a D, C. hammer.

electric hammer, 1 denotesthe intermediate portion and 2 and 3 the end portions of a Referring to the drawings in detail;

casing formediof any suitable non-magnetic material. The intermediate portion lis of less diameter than either of the end portions 2, 3, and provides a handle. Each of the end portions 2, 3, is open at its outer.l end, Interior threads are provided, as at 4, on eachend portion 2, 3. i f

The casing at it-s forward end is closed by gages with threads 4 of the end portion 2.

The .inner face of the disk 5, centrally thereof, has an annular boss 6, and its outer face, centrally thereof, an annular collar'7. The disk 5 is formedwith a centrally disposed openino 8 which extends through the boss 6 and co lar 7, and-has the wall thereof threaded. t Secured at one end in the collar 7 and project-ing forwardly from the disk 5, is a clamp 9, having an inset portion 10. The purpose of the clamp 9 will be" presently ferred to.

The casing at its rear endy is closed by a peripherally threaded head-piece 11, which engages with the threads 4 of the end portion 3. The inner face of the headpiece 11, centrally thereof, has a boss 12, and said head-piece 11 has a -centrally disposed pocket 13, which extends through the boss 12 and opens into the end 3 ofthe casing. The walltofthe pocket 13 is threaded. The head piece 11 -projects rearwardly from the end portion 3 ofthe casing and has formed integral therewith a hollow handle member 14.

The head-piece at one side carries a laterally extending nipple 15 which opens into the member 14, and also into a passage 16, formed in the head piece 11, at one sidelof the pocket 13. The nipple 1 5 is interiorly threaded and"isiclosed by a peripherally threaded hollowflanged plug 16a, the latter andy has secured therewith a cable 17, which encloses the leading-in-wires or conductors 18, 19, and switch wires 21, 22, these' latter extending into the hollow handle member 14. lThe wires 21, 22, are connected with the main operating switch of the device and which is in the form 4of a push-button 23, mounted in the member 14, operatedex-v teriorly thereof, and which is employed for throwing the mechanism into operation.

Engaging at onel end with the threads of the opening 8 and at its other end with the threads of the pocket 13, is a tube 24 of nonmagnetic `material. The tube 24 extends from the bottomof the pocket 13 to the coli lar 7, .and mounted thereon, within the end 32 extends into the tube 24, in the path of,

f the piston. b

portion- 2, is a solenoid 25, and withinthe end portion 3 is a solenoid 26.

Means to provide a magnetic circuit, associated with each solenoid,is arranged in each end portion 2, 3`, of the casing. By way of example said means consists of a set of magnetic cores 27 and 29, formed-of laminations of U-shape, secured together and overlapping the solenoids,` The means to provide the magnetic circuit associated with the solenoid 25v is indicated at 27, and extendsl from the boss 6, of the disk 5,to the inwardly extending flange 28 at the rear of the 'end portion 2. The means to provide the magnetic circuit with y,the solenoid 26 is indicated at 29, and `extends from the boss 12 of the head-piece 11, to the inwardly extending flange 30 at the front of the end portion 3. It will be stated however, that any form of means to provide the magnetic circuits can be employed, depending upon the type of hammer or device with whichV theldrive mechanism is associated.

Arranged within the tube/24,'is a reciproeating element 31, in the form of a reciproeating core, and which isfconstructed of any suitable magnetic material and the purpose of which is to impact against the shank 32 of a tool 33 to operate the latter. The shank The tool 33 is detacha y 'connected'with the' end portion 2, by the inset portion 10, of the clamp 9, engaging in a peripheral groove-34 on the tool 33. It will ,be stated however, that the -tool 33 can be connected with the end portion 2 inany suitable manner.

between the piston 31 and shank 32, a heli For the purpose of increasing. the impact cal spring 35 i's employed. The spring 35 is lfixedly secured to the heady-piece 11 and is arranged within that portion of the tube' 24 which extends into the pocket 13.

The lead 18 extends to the ysolenoid 25, the' lead 19 to the solenoid 26 and the lead 20 to a conductor 36 which bridges the solenoids 25 and ,26.

lThe switch, wires orY conductors extend from an operating switch of a circuit making and breaking device, 'arranged exteriorly of the hammer, to the switch or push button 23. f i

lin Figure 5 of the drawings which illustrates a diagram 0f the circuit arrangement of an A. C. hammer, A is the hammer, B a source of power connected with a circuit making and breaking device, E, F, operat- .fing switch, Gr switch or push-button, 18,

31 the reciprocating core, 21, 22 switch wires, G push button.

TheY operation of the mechanism is as follows Y Through the means of the"circuit making and breaking device exteriorly of the hammer, the current is m-ade to energize and cle-energize the solenoidsalternately; this causes an alternative attraction of the reciprocating core with respect to the two solenoids, thereby producing a reciprocatory motion of the reciprocating core. When traveling in one direction impact occurs between the reciprocating core and shank of the tool, thereby causing the latter to perform its function. When traveling in the opposite direction the reciprocating core compresses the helical spring causing energy to bel stored therein, which in turn is transferred to the reciprocating core and'` ywhich adds t0 the impact between lthe reciprocating core and the shank of the tool thus increasing the capacity of the latter to perform its `function.

The reciprocatory motion of the core 31,

is obtained in conjunction with the contractor E, Figure 5, as follows Upon closing the push button switch G, the coil s, of the magnet switch F, is energized, thereby closing` the 'circuit through conductor 20, coil 26, conductor 19, coil I), conductor 8, contacts d and g, and conduc tor/w, back to the source of supplyvB. The circuit is also closed through the conductor 20, coil 25,'conductor 18, coil` a, conductor fr, contacts 7" and z.' and conductor t, back to the source of suppl'yB.

With the core 31 positioned Aas shown,`

owing to the impedance'ofvthe coil 25, the energy in coil a is-insuicient to pull armature n into` coil a, to ope contact g from contact a? against spring l tacts g` and d will rem-am closed. But the impedance of coil 26, is such as to permit a, therefore .con-

of suiicient energy to pass through coil b, to

pull the armature n into coil b, against spring lc, closing contact h, on contacte,

thereby opening the circuit through the ductor 20, coil 26, conductor19, coil t, conergizing coil and coil a..

tacts e and L, conductora? back to the source ofvsupply B. The core 31 is thus caused to Vmove out of coil 25, into coil 26, increasingfthe impedance of .coil 26, and decreasing the energy through coil 5,' permitting spring lato pull armature m" out of coil b, thereby opening contact JL, from contact e, and instantaneously closing contact h, on contact f closing the circuit through conductor 20, coil 25, conductorl8, coil a, conductor 1', contacts' f and i, conductor t, and back to thesource of supply B, thereby en- The impedance of coil 25 is such to permit of suiicient energy through' coil a, to pull armature 'm into coil u against spring 2,

thereby opening contact g from contact d and instantaneously closing Contact g, on contact c, and closing the circuit through the conductor 20, coil 25, conductor 18, coil a, contacts c and gand conductor w back to the source of'supply B.

4On the instant that coil 26 is dev-energized and coil25 is energized, "the core 31 is caused toA move out of coil'26 into coil '25, thereby completing the cycle. Thus it will be seen that the number of oscillations of the core is limited only by its own inertia.

` o and p of contactor E, are contact arms and/v and a: arefulcrums. Contacter` E is shown diagrammatically and it `is understood that any type of contactor may be l an alternating current circuit comprisemployed.

The operation of lthis v.mechanism with arrangement shown in Figure 5, depends .upon the reactive effect in the various circuits produced by the core 31.

1. A reciprocating apparatus 'adapted .to be supplied from` an valterating current circuit, wherein a core is arranged to be repeatedly moved into and out of a solenoid and \wherein an electromagneticA switch means is arranged to alternately energize. and de-energize3 the solenoid, characterized by the fact that a winding of thenelectromagnetic switch is. connected in circuit with the solenoid toreduce the current in the winding and open the switchwhen the core is moved into the solenoid to increase the moved into theksolenoid, and an electromagalternately netic switch means arranged to alternately energizefand de-energize' the solenoid, said switch having a winding connected in circuit 'ing a pairiof solenoids, a -core adapted to alternately move into and out of each of the solenoids and to increase the reactance of the circuit when moved into,'a solenoid, and an electromagneticswitch means adapted to alternately energizeand de-energize the solenoids, said switch having a pair of windings leach connected-in circuit with a solenoid whereby when the core is moved into asolenoid the switch is opened by the increased reactance of the circuit.

4. A reciprocating apparatus operated from an alternating current circuit comprisi-ng a hollow member of "non-magnetic material a pair of solenoids mounted thereon and spaced from each other, a shiftable element of magnetic material arranged in said member and ladapted to alternately move into and out of each of the solenoids and to increase the reactance of the circuit when moved into a solenoid, laminated elements partially enclosing said solenoids and each uproviding an independent external magnetic circuit for it-s'associated solenoid, and an electromagnetic switch means adapted to energize vand de-energize the solenoids, said switch having a pair of windings eacli connected in circuit with-a solenoidwhereby when the shiftable element is moved into a solenoid the switch is opened by theincreased reactance of the circuit.

5. A reciprocating apparatusoperated ing a pair of solenoids, areciprocatory core alternately moving intoand out of said soleno1ds, an electro-magnetic switching mechanism, an independent conductor between each solenoid and said mechanism,

said mechanism including a pair` ot circuit opening and closing elements each in both circuits yand each actuated by ythe increased reactance 'created in a circuit when said cori-moves intoa solenoid whereby the circuit` of which the solenoid vformspart. is

opened and the circuit -of which the other' i solenoid forms part is closed thereby rocating the core.

6. A reciprocating apparatus operated from an alternating current circuit com-- recipprising a pair of solenoids, apair of electro- ,a

Jmagnetic switches each in circuit'with a sole-` noid and each common tovboth circuits, a

.core arranged t0 move alternatelyy into and out of each of .the solenoids whereby when moved into a solenoid the reactance of the circuit through said solenoid and its associated switch is increased thereby causiing said hitter switch to close the circuit through the other solenoid and its associated switch and to open the circuit of which the first mentioned solenoid is a part.

'7. In a reciprocating appara-tus operated by un alternating current circuit, a recipro- `catory core, an electro-magnetic element act'- ing)` on the core for reciprocating it, means to provide. a pnir of independent circuits consaid core moves in one direction to openl such circuit and to close the other circuit thereby shifting the oore in the opposite direction to create :in increased reaetance in the. last mentioned circuit to actuaie the other member to open such circuit and to close the rstmentioned circuit to shift the core in the other direction.

iIn testimony whereof I aix my signature inthe presence of two witnesses.

` GEORGE E. HAMPTON.

Witnesses:

MAX H; SooLoNrr, LUELLA H. SIMON'. 

